Correlating corrosion modes with the microstructure of the 2XXX series alloys: A comparative approach

Abstract

In this study, the localized corrosion susceptibility of AA2050‐T84, AA2198‐T851, and AA2024‐T3 alloys was compared by immersion in three test solutions, specifically sodium chloride solution (3.5% NaCl), EXCO solution, according to ASTM G34‐18, and a solution for intergranular corrosion (IGC) test recommended by ASTM G110‐15 and via scanning vibrating electrode technique (SVET). The results showed higher susceptibility of AA2050‐T84 alloy to all types of corrosion tested compared to the other studied 2XXX series alloys. Corrosion penetration was deeper in the AA2050‐T84 due to its microstructural characteristics as a difference in the micrometric Cu‐Rich intermetallic particle distribution on the surface and related to the distribution of the T1 (Al2CuLi) phase.